McKee had treated Laurion’s father after a stroke, and Laurion thought the doctor was rude and insensitive. “When I mentioned Dr. McKee’s name to a friend who is a nurse, she said, ‘Dr. McKee is a real tool!’ ” Laurion wrote.

None of the statements were actionable, the supreme court said, because there was no proof they were false or capable of harming reputation. The “real tool” assertion was protected as a statement of pure opinion under the First Amendment, Justice Alan Page wrote in the opinion (PDF).

“Referring to someone as ‘a real tool’ falls into the category of pure opinion because the term ‘real tool’ cannot be reasonably interpreted as stating a fact and it cannot be proven true or false,” he said. “We conclude that it is an opinion amounting to ‘mere vituperation and abuse’ or ‘rhetorical hyperbole’ that cannot be the basis for a defamation action.”

Laurion’s lawyer, John Kelly, told the Star Tribune that the court’s ruling was based on a defamation analysis; the fact that the statements were made online did not affect the result. The principles “are applicable to statements made irrespective of the medium,” he told the newspaper.